In a combustion engine, air from the surrounding atmosphere is introduced to the engine to mix with fuel in the combustion chamber. Dirty and/or contaminated intake air may not only affect the engine performance, but also damage moving parts of the engine, resulting in increased maintenance costs and reduced life of the engine. To ensure the cleanliness of the intake air, an air filter is used to filter out dirt, debris, and other contaminants from the intake air.
Off-highway machines, such as, for example, tractors, wheel loaders, backhoe loaders, bulldozers, and excavators, may operate in and be exposed to harsh working environments with high concentrations of dust and debris. The air filters used in these machines offer high strength to withstand the vibrations expected in the machines and high dirt-holding capacity to adequately protect the engine for the desired service life of the filter elements. Accordingly, these machines are equipped with a relatively large air filter. An air filter may include an air filter element and a filter housing for housing and protecting the air filter element.
Typically, machine air filters are replaced based on a predetermined number of set hours of use and/or a worst-case scenario. The determination of such set hours of use is based on generic filter types and is not specific to the type of filter being considered for replacement. However, different filters have different rates at which they get loaded with particles, and applying a generic conventional scheme to replace the filter based on the hours of use may result foregoing opportunities in operating cost. Further, even for the same filter type, each individual filter has a different loading rate depending upon usage and other environmental factors. Therefore, replacing a filter based upon an hours of usage may not fully utilize the actual operable life of the filter.
Some conventional systems use an electronic control module (ECM) to calculate the pressure differential (P) across a filter, and then use an algorithm to calculate the condition of the filter from the pressure differential. See, for example, U.S. Patent Application Publication No. 2004/0217872. However, such algorithms may not be accurate.
Accordingly, there is a need to resolve these and other problems related to the conventional filter health and remaining useful life prediction techniques.